The present invention relates to an apparatus and method of forming and curing fiber reinforced plastic composite structural parts using in combination, temperature and controlled pressure.
Prior to the present invention the method used to form a structural part, from a material such as graphite/epoxy, was to lay up the material on a fixture or a flat table and subsequently transfer it to a bonding fixture. The part, together with its bonding fixture, was then vacuum bagged using either a butyl or silicone rubber bag. After bagging, the part was debulked by vacuum means to remove entrapped air and the assembly with vacuum applied was transferred to a temperature controlled chamber for curing. After curing, the assembly was removed from the temperature controlled chamber and allowed to cool before removing the part. The basic shortcomings of the above prior art method are: (1) the part must be vacuum bagged to remove entrapped air from between the layups of material, (2) means are not provided to bleed the part for removal of excess resins while the part is being formed, and (3) a combination of variable control pressure and temperature is not applied to the part during the cure cycle.